The 3rd Generation Partnership Project (3GPP) is standardizing Sakai-Kasahara Key Encryption in Multimedia Internet KEYing (MIKEY-SAKKE) for communication devices that communicate in accordance with the 33.179 Security of Mission Critical Push-To-Talk (MCPTT) specification. MIKEY-SAKKE and other key management schemes often rely on periodic key renewal to enhance security. However, many key management schemes do not include mechanisms for handling security compromised communication devices. As a result, push-to-talk groups with one or more security compromised communication devices cannot securely communicate because identity-based cryptographic private keys are not updated or revoked until the next scheduled key renewal period.
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The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.